• Archives of Pharmacal Research
• /
• v.20 no.6
• /
• pp.597-601
• /
• 1997

An oxidimetric titrant, 2, 3-dichloro-5, 6-dicyano-1, 4-benzoquinone in anhydrous acetic acid is used for the semimicro-determination of hydrazine hydrate, phenylhydrazine hydrochloride, isoniazid and iproniazid phosphate in pure forms as well as in some pharmaceutical preparations containing isoniazid and iproniazid phosphate. The end point was detected potentiometrically using a platinum-calomel combination electrode. The results obtained are compared statistically with those obtained by the official methods and they are in good agreement.

• Journal of the Korean Chemical Society
• /
• v.19 no.6
• /
• pp.443-448
• /
• 1975

A series of 9,10-dialkyl-9,10-dihydroanthracene has been dehydrogenated by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) in good yields. The yield decreased with the larger alkyl groups in this 9,10-dialkyl-9,10-DHA series(DHA=dihydroanthracene). It is conceivable that trans-9,10-diisopropyl-9,10-DHA was dehydrogenated more rapidly than the cis-isomer, and, bassed on this observation, a concerted mechanism was ruled out and an ionic mechanism is proposed.

• Journal of Photoscience
• /
• v.12 no.2
• /
• pp.109-111
• /
• 2005

It was found that 1,4-diketones such as 1,4-diphenyl-l,4-butanediones containing N,N-dimethylaminophenyl (pDPB) and N,N-dimethylaminonaphthyl (nDPB) at C2 are converted into 3-(4-dimethylaminoaryl)-1-phenylpropan-lones (pPPA and nPPA) by treatment with $Ca(OH)_2$ in methanol, which was easily oxidized to enone, i.e., 3-(4-dimethylaminophenyl)-l-phenylpropenones (pPPE and nPPE), when treated with 2,3-dichloro-5,6-dicyano-l,4-benzoquinone (DDQ) in dichloromethane.

• YAKHAK HOEJI
• /
• v.49 no.6
• /
• pp.443-448
• /
• 2005

Diosgenin (25 (R) - spirost-5-en-3$\beta$ -ol) was oxidized with 2,3-dichloro -5,6-dicyano-1,4-benzoquinone to form 25(R)-1,4,6-spirostatrien-3-one (1) as rigid cyclic $\alpha$,$\beta$-unsaturated carbonyl compound. This compound was reacted with $H_{2}O_{2}$, m-chloroperoxybenzoic acid (mCPBA), NaOCl in the presence with (R,R)- or (S,S)-Jacobsen catalyst, tert-butyl-hydroperoxide (TBHP) in Mo$(CO)_{6}$, and in VO $(acac)_{2}$ catalyst, respectively, 25(R) -1,4,6-spirostatrien -3-one (1) was reduced with $NaBH_{4}$ L-Selectride, $LiAIH_{4}$,$BH_{3}$ $\cdot$$(CH_{3})_{2}S$, Superhydride, Red-Al, and lithium tri-tert-butoxyaluminium hydride. And 25(R)-4,6-spirostadien-3$\beta$-ol (4) was treated with $H_{2}O_{2}$, mCPBA, TBHP in D - (-) - and L-(+)-diisopropyltar-trate and $Ti(OiPr)_{4}$ condition (Sharpless asymmetric epoxidation), TBHP in $Mo(CO)_{6}$, and in $VO(acac)_{2}$ catalyst, respectively.

• Journal of the Korean Wood Science and Technology
• /
• v.25 no.3
• /
• pp.1-7
• /
• 1997

한국산 동백나무겨우살이(Pseudixus japonicus Hayata)에 존재하는 수용성 리그닌-탄수화물 복합체를 구성하는 다당류의 구조를 밝히고 리그닌 성분과 다당류의 결합양식을 구명하고자, 냉 온수 추출한 수용성 리그닌-탄수화물 복합체(M-LCC-WE)를 DEAE Sephadex A-50로 중성분획(M-LCC-N)과 산성분획(M-LCC-A), 나머지분획(M-LCC-R)으로 세분화한 후 M-LCC-N과 M-LCC-A에 대하여 메틸화, 아세틸화, 그리고 DDQ 산화반응을 실시하였다. M-LCC-N을 구성하는 다당류는 ($1{\rightarrow}4$) 글리코시드결합의 arabinan과 ($1{\rightarrow}4$)나 ($1{\rightarrow}6$) 글리코시드결합의 galactan과 glucan으로 M-LCC-A의 다당류는 ($1{\rightarrow}4$) 글리코시드결합의 arabinan과 ($1{\rightarrow}6$) 글리코시드결합의 galactan이 다당류 주성분으로 밝혀졌으며 galacturonic acid가 결합되어 있기 때문에 산성적 성질을 나타내고 있었다. 또한 M-LCC-A에서는 galacturonic acid 의 carboxyl 그룹이 리그닌의 ${\alpha}$-와 ${\gamma}$-위치에서 ester결합이 존재함이 확인되었다.